Lipkin & Silva (2002: 53, 54) record Ulva lactuca sensu lato nec Linnaeus, growing on Laurencia, from Entedebir Island, Dahlak Archipelago. They note that it is possible that the eastern Mediterranean and Red Sea plants may represent a separate species but add that the relationships between the different Ulva populations of this extensive region should be clarified before any new names are proposed. - (16 Jun 2010) - Wendy Guiry

Delnatte & Wynne (2016) note "The traditional concepts of Ulva fasciata and U. lactuca are being retained in this treatment. Brief notes appeared in Science (Holden 2007) and in Nature (Butler 2007) with preliminary results indicating that genome mapping conducted by C.Maggs and F.Mineur on the type of U. lactuca in the Linnean Herbarium revealed that the map matched that which was known for U. fasciata. An in-depth official publication of their results has not yet been published." - (20 Oct 2016) - M.D. Guiry

Type informationType locality: "in Oceano" [Atlantic Ocean] (Linnaeus 1753: 1163). Lectotype: LINN 1275.24 Notes: According to Womersley (1984: 141) the type is from the west coast of Sweden. The type is marked "5" and agrees well with Linnaeus's description, and the number five is assigned to Ulva lactuca in Species plantarum (Papenfuss 1960).